A method for growing multilayer quantum dot lasers based on stress compensation technology

Abstract

A method for growing a multilayer quantum dot laser based on stress compensation technology, comprising: S1, removing an oxide layer from an N-type substrate, and performing N-type GaAs buffer layer, N-type Al v Ga 1‑v As confinement layer and GaAs waveguide layer 1 are grown; S2, In w Ga 1‑w As quantum wells, InAs quantum dots, In x Ga 1‑x As cap layer, GaAs cap layer, GaAs spacer layer 1, etc. are grown; S3, S2 is cycled for a set number of times to achieve the growth of multi-layer quantum dot materials; S4, GaAs waveguide layer 2, P-type Al z Ga 1‑z As limiting layer and P-type GaAs metal contact layer are grown. The present invention utilizes GaAsP material with a smaller lattice constant to reduce the stress brought by InGaAs material, so as to improve the uniformity and quality of the multi-layer quantum dot laser structure.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor lasers, and in particular to a multi-layer quantum dot laser growth method based on stress compensation technology. Background Art

[0002] With the development of optical interconnection technology and the Internet of Things, there is a huge demand for the performance requirements of lasers in optical circuits in terms of temperature, output power, modulation rate, noise resistance, etc. Among them, 1.3μm and 1.55μm lasers based on GaAs and In play an extremely important role in optical communication systems with space optical communication and optical fiber communication as the main technologies. Compared with traditional quantum well lasers, quantum dot lasers can maintain ultra-low prediction while maintaining the high temperature characteristics, wall climbing efficiency and power output of the device due to their unique band structure.

[0003] Since InAs composite compound semiconductor materials are needed as light-emitting materials in both 1.3μm and 1.55μm quantum dot lasers, it is necessary to grow multiple layers of quantum dot materials to increase the gain of the laser itself to increase the output power and modulation rate. Especially in surface-emitting lasers, since the gain of quantum dots in the longitudinal direction is weak, multiple layers of quantum dot materials are needed to increase the gain. Then, when epitaxial growth is performed on GaAs and InP substrates, compared with GaAs and InP materials, InAs materials have a larger lattice coefficient, so a certain degree of stress accumulation is inevitable. When the stress reaches a certain thickness, it will release and produce crystal defects to form non-radiative load centers, thus affecting the luminescence performance of quantum dots. At the same time, due to the effect of stress release, in the growth of multi-layer InAs quantum dot materials, its uniformity will be negatively affected as the number of quantum dot layers increases, thereby affecting the performance of quantum dot lasers as a whole. So far, 1.3μm InAs quantum dot lasers based on GaAs substrates are prone to a certain degree of performance degradation when reaching more than ten layers due to the large number of dislocation defects, making it impossible to achieve high-power quantum dot lasers. Summary of the invention

[0004] The present invention provides a multi-layer quantum dot laser growth method based on stress compensation technology to solve the technical problems mentioned in the background technology.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] The present invention provides a method for growing a multilayer quantum dot laser based on stress compensation technology, comprising the following steps:

[0007] S1, remove the oxide layer of the N-type substrate, and respectively perform N-type GaAs buffer layer and N-type Al v Ga 1-v As confinement layer and GaAs waveguide layer are grown;

[0008] S2, In on the GaAs waveguide layer w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-x As cap layer, GaAs cap layer, GaAs spacer layer 1, P-type GaAs y P 1-y Growth of cap layer and GaAs spacer layer 2;

[0009] S3, cycle S2 for a set number of times, thereby achieving the growth of multi-layer quantum dot materials;

[0010] S4, GaAs waveguide layer 2, P-type Al z Ga 1-z As confinement layer and P-type GaAs metal contact layer are grown.

[0011] Furthermore, the substrate is a GaAs substrate.

[0012] Furthermore, the S1 specifically includes the following steps:

[0013] S11, placing the N-type GaAs substrate into a III-V material molecular beam epitaxy cavity, and raising the temperature in the cavity to 500-700° C. to remove an oxide layer on the surface of the N-type GaAs substrate;

[0014] S12. On the N-type GaAs substrate after removing the oxide layer, a 20-500 nm thick N-type doped GaAs buffer layer was grown using molecular beam epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C. The N-type doping concentration was 1×10 17 ~1×10 19 cm -3 ;

[0015] S13, using molecular beam epitaxy technology on the GaAs buffer layer at a growth rate of 0.1~1 ML / s at a chamber temperature of 500~700°C to grow 200~2000nm thick N-type doped Al v Ga 1-v As restricts the growth of the layer, in which the v component is 20%~90% and the concentration of N-type doping is 1×10 17 ~1×10 19 cm -3;

[0016] S14, in Al v Ga 1-v Molecular beam epitaxy is used on the As confinement layer to grow a non-intentionally doped GaAs waveguide layer with a thickness of 20~500nm at a growth rate of 0.1~1ML / s at an intracavity temperature of 500~700°C.

[0017] Furthermore, the temperature in the cavity in S11 is 610°C.

[0018] Furthermore, the temperature in the chamber of S12 is 580°C; the concentration of N-type doping in S12 is 5×10 18 cm -3 .

[0019] Furthermore, the temperature in the chamber of S13 is 600°C; the concentration of N-type doping in S13 is 2×10 18 cm -3 .

[0020] Furthermore, the S2 specifically includes the following steps:

[0021] S21. On the GaAs waveguide layer 1 or GaAs spacer layer 2, use molecular epitaxy technology at a growth rate of 0.1-1 ML / s at a cavity temperature of 400-550°C to grow a 1-5 nm thick non-intentionally doped In w Ga 1-w As quantum well growth, where the w component is 10%-30%;

[0022] S22.In w Ga 1-w Molecular epitaxy was used on As quantum wells to grow 2-4 monoatomic layers of unintentionally doped InAs quantum dots at a growth rate of 0.1-0.2 ML / s at a cavity temperature of 400-550°C.

[0023] S23, using molecular epitaxy technology on InAs quantum dots at a growth rate of 0.1~1 ML / s at a chamber temperature of 400~550°C to grow 3~8nm thick InAs without intentional doping x Ga 1-x As cap layer growth, in which the x component is 10%-30%;

[0024] S24. In x Ga 1-x The As cap layer is grown using molecular epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 400-550°C to form a 5-10 nm thick non-intentionally doped GaAs cap layer.

[0025] S25, growing a non-intentionally doped GaAs spacer layer 1 with a thickness of 10-20 nm on the GaAs cap layer using molecular epitaxy technology at a growth rate of 0.1-1 ML / s at a cavity temperature of 500-700° C.;

[0026] S26, using molecular epitaxy technology on the GaAs spacer layer, a 5~10nm thick P-type doped GaAs is grown at a growth rate of 0.1~1 ML / s at a chamber temperature of 400-600°C. y P 1-y Cap layer growth to offset In w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-x The stress caused by the As cap layer; the y component is 50%~90%, and the doping concentration is 1×10 17 ~1×10 19 cm -3 ;

[0027] S27, in GaAs y P 1-y Molecular epitaxy is used on the cap layer to grow a non-intentionally doped GaAs spacer layer 2 with a thickness of 10-20 nm at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C.

[0028] Furthermore, the setting number of times in S3 is 5 to 50 times.

[0029] Furthermore, the S4 specifically includes the following steps:

[0030] S41, growing a non-intentionally doped GaAs waveguide layer 2 with a thickness of 20-500 nm on the GaAs spacer layer 2 using molecular beam epitaxy technology at a growth rate of 0.1-1 ML / s at a cavity temperature of 500-700° C.;

[0031] S42, using molecular beam epitaxy technology on the GaAs waveguide layer 2, a 200~2000 nm thick P-type doped Al layer is grown at a growth rate of 0.1~1 ML / s at a cavity temperature of 500~700°C. z Ga 1-z As restricts the growth of the layer, in which the z component is 20%~90% and the concentration of P-type doping is 1×10 16 ~1×10 19 cm -3 ;

[0032] S43, in Al z Ga1-z The P-type doped GaAs metal contact layer with a thickness of 20-500 nm was grown on the As confinement layer using molecular beam epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C. The P-type doping concentration was 1×10 18 ~5×10 19 cm -3 .

[0033] Furthermore, the concentration of P-type doping in S42 is 5×10 17 cm -3 ; The concentration of P-type doping in S43 is 2×10 19 cm -3 .

[0034] Beneficial effects of the present invention:

[0035] The present invention proposes a method for growing a multilayer quantum dot laser based on stress compensation technology, which utilizes a layer of GaAsP material attached to the spacer layer of each quantum dot layer, the GaAsP material being GaAs spacer layer one and GaAs spacer layer two, thereby reducing the stress generated by heterogeneous growth of large lattice constants and the stress generated by InAs and InGaAs materials, realizing the growth of a stress-free laser active region, so that the prepared multilayer quantum dot laser has the advantages of high uniformity, high crystal quality and low defect density.

[0036] In addition, the present invention also discloses a laser active region, including In w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-x As cap layer, GaAs cap layer, GaAs spacer layer 1, P-type GaAs y P 1-y Cap layer and GaAs spacer layer 2; the laser active region can be used not only in ridge waveguide lasers, but also in surface emitting lasers to provide higher gain in the TM mode and thus enhance the laser effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a layout diagram of each layer in the multi-layer quantum dot laser of the present invention. DETAILED DESCRIPTION

[0038] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present invention are provided in the drawings. However, the present invention can be implemented in many other different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0040] Reference Figure 1 The present application embodiment provides a method for growing a multilayer quantum dot laser based on stress compensation technology, comprising the following steps:

[0041] S1, remove the oxide layer of the N-type substrate, and respectively perform N-type GaAs buffer layer and N-type Al v Ga 1-v As confinement layer and GaAs waveguide layer are grown;

[0042] S2, In on the GaAs waveguide layer w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-x As cap layer, GaAs cap layer, GaAs spacer layer 1, P-type GaAs y P 1-y The cap layer and the second GaAs spacer layer are grown to achieve the growth of the laser active region;

[0043] S3, cycle S2 for a set number of times, thereby achieving the growth of multi-layer quantum dot materials;

[0044] S4, GaAs waveguide layer 2, P-type Al z Ga 1-z As confinement layer and P-type GaAs metal contact layer are grown.

[0045] In some embodiments, the substrate is a GaAs substrate.

[0046] In some embodiments, the S1 specifically includes the following steps:

[0047] S11, placing the N-type GaAs substrate into a III-V material molecular beam epitaxy cavity, and raising the temperature in the cavity to 500-700° C. to remove an oxide layer on the surface of the N-type GaAs substrate;

[0048] S12. On the N-type GaAs substrate after removing the oxide layer, a 20-500 nm thick N-type doped GaAs buffer layer was grown using molecular beam epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C. The N-type doping concentration was 1×10 17 ~1×10 19 cm -3 ;

[0049] S13, using molecular beam epitaxy technology on the GaAs buffer layer at a growth rate of 0.1~1 ML / s at a chamber temperature of 500~700°C to grow 200~2000nm thick N-type doped Al v Ga 1-v As restricts the growth of the layer, in which the v component is 20%~90% and the concentration of N-type doping is 1×10 17 ~1×10 19 cm -3 ;

[0050] S14, in Al v Ga 1-v Molecular beam epitaxy is used on the As confinement layer to grow a non-intentionally doped GaAs waveguide layer with a thickness of 20~500 nm at a growth rate of 0.1~1 ML / s at an intracavity temperature of 500~700°C.

[0051] In some embodiments, the temperature inside the cavity in S11 is 610°C.

[0052] In some embodiments, the temperature in the cavity in S12 is 580°C.

[0053] In some embodiments, the concentration of the N-type doping in S12 is 5×10 18 cm -3 .

[0054] In some embodiments, the temperature in the cavity in S13 is 600°C.

[0055] In some embodiments, the S13 inner Al v Ga 1-v The value of v in the As limiting layer is preferably 40%, i.e. v Ga 1-v The As confinement layer is preferably Al 0.4 Ga 0.6 As restriction layer.

[0056] In some embodiments, the concentration of the N-type doping in S13 is 2×10 18 cm -3 .

[0057] In some embodiments, the thickness of the GaAs waveguide layer 1 in S14 is 100 nm.

[0058] In some embodiments, S2 specifically includes the following steps:

[0059] S21. On the GaAs waveguide layer 1 or GaAs spacer layer 2, use molecular epitaxy technology at a growth rate of 0.1~1 ML / s at a cavity temperature of 400~550°C to grow a 1~5 nm thick non-intentionally doped In w Ga 1-w As quantum well growth, where the w component is 10%-30%;

[0060] S22.In w Ga 1-w Molecular epitaxy was used on As quantum wells to grow 2-4 monoatomic layers (ML) thick, non-intentionally doped InAs quantum dots at a growth rate of 0.1-0.2 ML / s at a cavity temperature of 400-550°C.

[0061] S23, using molecular epitaxy technology on InAs quantum dots at a growth rate of 0.1~1 ML / s at a chamber temperature of 400~550°C to grow 3~8nm thick InAs without intentional doping x Ga 1-x As cap layer growth, in which the x component is 10%-30%;

[0062] S24. In x Ga 1-x The As cap layer is grown using molecular epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 400-550°C to form a 5-10 nm thick non-intentionally doped GaAs cap layer.

[0063] S25, growing a non-intentionally doped GaAs spacer layer 1 with a thickness of 10-20 nm on the GaAs cap layer using molecular epitaxy technology at a growth rate of 0.1-1 ML / s at a cavity temperature of 500-700° C.;

[0064] S26, using molecular epitaxy technology on the GaAs spacer layer, a 5-10 nm thick P-type doped GaAs is grown at a growth rate of 0.1-1 ML / s at a chamber temperature of 400-600°C. y P 1-y Cap layer growth to offset In w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-xThe stress caused by the As cap layer; the y component is 50%~90%, and the doping concentration is 1×10 17 ~1×10 19 cm -3 ;

[0065] S27, in GaAs y P 1-y Molecular epitaxy is used on the cap layer to grow a non-intentionally doped GaAs spacer layer 2 with a thickness of 10-20 nm at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C.

[0066] In some embodiments, the S21 w Ga 1-w The value of w in the As quantum well is preferably 18%, that is, In w Ga 1-w As quantum wells are preferably In 0.18 Ga 0.82 As quantum well.

[0067] In some embodiments, the temperature in the S21 cavity is preferably 510°C.

[0068] In some embodiments, the S21 w Ga 1-w The thickness of the As quantum well without intentional doping is preferably 2 nm.

[0069] In some embodiments, the temperature in the S22 cavity is preferably 510°C.

[0070] In some embodiments, the thickness of the InAs quantum dots in S22 without intentional doping is preferably 3 monoatomic layers (ML).

[0071] In some embodiments, the temperature in the cavity of S23 is preferably 510°C.

[0072] In some embodiments, the S23 x Ga 1-x The value of x in the As cap layer is preferably 18%, that is, In x Ga 1-x As cap layer is preferably In 0.18 Ga 0.82 As cap layer.

[0073] In some embodiments, the S23 x Ga 1-x The thickness of the As cap layer without intentional doping is preferably 5 nm.

[0074] In some embodiments, the temperature in the cavity of S24 is preferably 510°C.

[0075] In some embodiments, the thickness of the GaAs cap layer without intentional doping in S24 is preferably 10 nm.

[0076] In some embodiments, the temperature in the cavity of S25 is preferably 580°C.

[0077] In some embodiments, the thickness of the GaAs spacer layer 1 in S25 is preferably 10 nm.

[0078] In some embodiments, the temperature in the S26 cavity is preferably 520°C.

[0079] In some embodiments, the GaAs in S26 y P 1-y The thickness of the P-type doped cap layer is preferably 5 nm.

[0080] In some embodiments, the S26 GaAs y P 1-y The value of y in the cap layer is preferably 80%, that is, GaAs y P 1-y The cap layer is preferably GaAs 0.8 P 0.2 Cover layer.

[0081] In some embodiments, the GaAs in S26 y P 1-y The doping concentration of the cap layer P-type doping is preferably 5 × 10 17 cm -3 .

[0082] In some embodiments, the temperature in the S27 cavity is preferably 580°C.

[0083] In some embodiments, the thickness of the second GaAs spacer layer without intentional doping in S27 is preferably 10 nm.

[0084] In some embodiments, the set number of times in S3 is 5 to 50 times. Preferably, the set number of times is 20 times.

[0085] In some embodiments, the S4 specifically includes the following steps:

[0086] S41, growing a non-intentionally doped GaAs waveguide layer 2 with a thickness of 20-500 nm on the GaAs spacer layer 2 using molecular beam epitaxy technology at a growth rate of 0.1-1 ML / s at a cavity temperature of 500-700° C.;

[0087] S42, using molecular beam epitaxy technology on the GaAs waveguide layer 2 at a growth rate of 0.1~1 ML / s at a cavity temperature of 500~700°C, a 200~2000nm thick P-type doped Al z Ga 1-z As restricts the growth of the layer, in which the z component is 20%~90% and the concentration of P-type doping is 1×10 16 ~1×10 19 cm -3 ;

[0088] S43, in Al z Ga 1-z The P-type doped GaAs metal contact layer with a thickness of 20-500 nm was grown on the As confinement layer using molecular beam epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C. The P-type doping concentration was 1×10 18 ~5×10 19 cm -3 .

[0089] In some embodiments, in order to reduce the loss caused by free carrier absorption and provide sufficient carriers, the concentration of P-type doping in S42 is preferably 5×10 17 cm -3 .

[0090] In some embodiments, to achieve high crystal quality growth, the chamber temperature in S43 is preferably 600°C.

[0091] In some embodiments, the S42 is Al z Ga 1-z The value of z in the As limiting layer is 40%, that is, Al z Ga 1-z The As confinement layer is preferably Al 0.4 Ga 0.6 As restriction layer.

[0092] In some embodiments, in order to achieve ohmic contact with the electrode, the concentration of the P-type doping in S43 is preferably 2×10 19 cm -3 .

[0093] In some embodiments, the temperature in the cavity in S43 is preferably 580°C.

[0094] For ease of understanding, the following examples are given below to illustrate;

[0095] Step 1, placing an N-type GaAs substrate into a III-V material molecular beam epitaxy chamber, and raising the temperature in the chamber to 610° C. to remove the oxide layer on the surface of the N-type GaAs substrate, and using a molecular beam epitaxy device to perform the following growth;

[0096] Step 2: On the N-type GaAs substrate after removing the oxide layer, a 200 nm thick N-type doped GaAs buffer layer is grown using molecular beam epitaxy at a chamber temperature of 580°C to improve the flatness of the GaAs material. To achieve effective metal ohmic contact, the N-type doping concentration is 5×10 18 cm -3 ;

[0097] Step 3: To achieve high crystal quality growth, N-type doping of Al2O3 on the GaAs buffer layer was performed at a chamber temperature of 600°C. 0.4 Ga 0.6 As restricts the growth of the layer, and the concentration of N-type doping is 2×10 18 cm -3 ;

[0098] Step 4: In Al 0.4 Ga 0.6 A non-intentionally doped GaAs waveguide layer with a thickness of 100 nm is grown on the As confinement layer at a cavity temperature of 580°C to confine the longitudinal mode of the laser.

[0099] Step 5: growing a multilayer laser active region on the GaAs waveguide layer 1, including from the laser active region 1 to the laser active region N; each layer of the laser active region includes In w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-x As cap layer, GaAs cap layer, GaAs spacer layer 1, P-type GaAs y P 1-y Cap layer and GaAs spacer layer 2; the growth process of the laser active region, i.e. S2;

[0100] Specifically, step 5 includes the following steps:

[0101] Step 51: grow a 2 nm thick layer of unintentionally doped In on the GaAs waveguide layer at a cavity temperature of 510°C. 0.18 Ga 0.82 As quantum well;

[0102] Step 52: In 0.18 Ga 0.82On the As quantum well, a 3ML thick non-intentionally doped InAs material is grown at a cavity temperature of 510°C to form InAs quantum dots.

[0103] Step 53: grow a 5 nm thick layer of unintentionally doped In on the InAs quantum dots at a temperature of 510°C in the cavity. 0.18 Ga 0.82 As cap layer;

[0104] Step 54: In 0.18 Ga 0.82 A non-intentionally doped GaAs cap layer with a thickness of 10 nm was grown on the As cap layer at a chamber temperature of 510°C.

[0105] Step 55, growing a non-intentionally doped GaAs spacer layer 1 with a thickness of 10 nm on the GaAs cap layer at a chamber temperature of 580° C.;

[0106] Step 56: Grow a 5 nm thick P-type doped GaAs layer on the GaAs spacer layer at a temperature of 520°C in the chamber. 0.8 P 0.2 The cap layer has a P-type doping concentration of 5 × 10 17 cm -3 ;

[0107] Step 57: In GaAs 0.8 P 0.2 A non-intentionally doped GaAs spacer layer 2 with a thickness of 10 nm is grown on the cap layer at a chamber temperature of 580°C;

[0108] Step 6, and repeat steps 51 to 57 for a total of 20 times to form 20 layers of laser active regions (or InAs quantum dot active region structures);

[0109] Step 7, using molecular beam epitaxy technology to grow a non-intentionally doped GaAs waveguide layer 2 with a thickness of 20-500 nm on the GaAs spacer layer 2 in the laser active region at a growth rate of 0.1-1 ML / s at a cavity temperature of 500-700° C.;

[0110] Step 8: Grow P-type doped Al on the GaAs waveguide layer 2 at a cavity temperature of 600°C. 0.4 Ga 0.6 As confinement layer, the concentration of P-type doping is 5×10 17 cm -3 ;

[0111] Step 9: In Al 0.4 Ga 0.6The N-type doped GaAs metal contact layer was grown on the As confinement layer at a temperature of 580°C in the chamber. The N-type doping concentration was 2×10 19 cm -3 .

[0112] The purpose of the present invention is to realize and prepare a multilayer quantum dot laser based on an N-type GaAs substrate. The number of layers in the active region of the laser can exceed 20 layers, and the uniformity of the quantum dot material can be maintained. The method successfully solves the problem of performance degradation of the multilayer quantum dot laser due to stress accumulation, and provides a method for manufacturing a quantum dot laser with high output power, high gain, high temperature, low threshold and long life.

[0113] In order to compensate for the stress generated by InAs and InGaAs materials during the growth of InAs quantum dot materials, the present invention designs a layer of GaAsP material attached to the spacer layer of each quantum dot layer, the GaAsP material is GaAs spacer layer 1 and GaAs spacer layer 2, thereby reducing the stress generated by large lattice constant heterogeneous growth and the stress generated by InAs and InGaAs materials, and realizing the growth of stress-free laser active area.

[0114] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered within the protection scope of the present invention. In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for growing a multilayer quantum dot laser based on stress compensation technology, characterized in that: The steps include: S1, remove the oxide layer of the N-type substrate, and respectively perform N-type GaAs buffer layer and N-type Al v Ga 1-v As confinement layer and GaAs waveguide layer are grown; v component is 20%~90%; S2, In on the GaAs waveguide layer w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-x As cap layer, GaAs cap layer, GaAs spacer layer 1, P-type GaAs y P 1-y Growth of cap layer and GaAs spacer layer 2; S3, cycle S2 for a set number of times, thereby achieving the growth of multi-layer quantum dot materials; S4, GaAs waveguide layer 2, P-type Al z Ga 1-z As confinement layer and P-type GaAs metal contact layer growth; The substrate is a GaAs substrate.

2. The method for growing a multi-layer quantum dot laser according to claim 1, characterized in that: The S1 specifically includes the following steps: S11, placing the N-type GaAs substrate into a III-V material molecular beam epitaxy cavity, and raising the temperature in the cavity to 500-700° C. to remove an oxide layer on the surface of the N-type GaAs substrate; S12. On the N-type GaAs substrate after removing the oxide layer, a 20-500 nm thick N-type doped GaAs buffer layer was grown using molecular beam epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C. The N-type doping concentration was 1×10 17 ~1×10 19 cm -3 ; S13, using molecular beam epitaxy technology on the GaAs buffer layer at a growth rate of 0.1~1 ML / s at a chamber temperature of 500~700°C to grow 200~2000nm thick N-type doped Al v Ga 1-v As restricts the growth of the layer, in which the v component is 20%~90% and the concentration of N-type doping is 1×10 17 ~1×10 19 cm -3 ; S14, in Al v Ga 1-v Molecular beam epitaxy is used on the As confinement layer to grow a non-intentionally doped GaAs waveguide layer with a thickness of 20~500 nm at a growth rate of 0.1~1 ML / s at an intracavity temperature of 500~700°C.

3. The method for growing a multi-layer quantum dot laser according to claim 2, characterized in that: The temperature inside the cavity in S11 is 610°C.

4. The method for growing a multi-layer quantum dot laser according to claim 2, characterized in that: The temperature in the cavity of S12 is 580°C; the concentration of N-type doping in S12 is 5×10 18 cm -3 .

5. The method for growing a multi-layer quantum dot laser according to any one of claims 2 to 4, characterized in that: The temperature in the chamber of S13 is 600°C; the concentration of N-type doping in S13 is 2×10 18 cm -3 .

6. The method for growing a multi-layer quantum dot laser according to claim 1, characterized in that: The S2 specifically includes the following steps: S21. On the GaAs waveguide layer 1 or GaAs spacer layer 2, use molecular epitaxy technology at a growth rate of 0.1~1 ML / s at a cavity temperature of 400~550°C to grow a 1~5 nm thick non-intentionally doped In w Ga 1-w As quantum well growth, where the w component is 10%~30%; S22.In w Ga 1-w Molecular epitaxy was used on As quantum wells to grow 2-4 monoatomic layers of unintentionally doped InAs quantum dots at a growth rate of 0.1-0.2 ML / s at a cavity temperature of 400-550°C. S23, using molecular epitaxy technology on InAs quantum dots at a growth rate of 0.1~1 ML / s at a cavity temperature of 400~550°C to grow 3~8 nm thick InAs quantum dots without intentional doping. x Ga 1-x As cap layer growth, in which the x component is 10%-30%; S24. In x Ga 1-x The As cap layer is grown using molecular epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 400-550°C to form a 5-10 nm thick non-intentionally doped GaAs cap layer. S25, growing a non-intentionally doped GaAs spacer layer 1 with a thickness of 10-20 nm on the GaAs cap layer using molecular epitaxy technology at a growth rate of 0.1-1 ML / s at a cavity temperature of 500-700° C.; S26, using molecular epitaxy technology on the GaAs spacer layer, a 5-10 nm thick P-type doped GaAs is grown at a growth rate of 0.1-1 ML / s at a chamber temperature of 400-600°C. y P 1-y Cap layer growth to offset In w Ga 1-w As quantum wells, InAs quantum dots, In x Ga 1-x The stress caused by the As cap layer; the y component is 50%~90%, and the doping concentration is 1×10 17 ~1×10 19 cm -3 ; S27, in GaAs y P 1-y Molecular epitaxy is used on the cap layer to grow a non-intentionally doped GaAs spacer layer 2 with a thickness of 10-20 nm at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C.

7. The method for growing a multi-layer quantum dot laser according to claim 1, characterized in that: The setting number in S3 is 5 to 50 times.

8. The method for growing a multi-layer quantum dot laser according to claim 1, characterized in that: The S4 specifically includes the following steps: S41, growing a non-intentionally doped GaAs waveguide layer 2 with a thickness of 20-500 nm on the GaAs spacer layer 2 using molecular beam epitaxy technology at a growth rate of 0.1-1 ML / s at a cavity temperature of 500-700° C.; S42, using molecular beam epitaxy technology on the GaAs waveguide layer 2 at a growth rate of 0.1~1 ML / s at a cavity temperature of 500~700°C, a 200~2000nm thick P-type doped Al z Ga 1-z As restricts the growth of the layer, in which the z component is 20%~90% and the concentration of P-type doping is 1×10 16 ~1×10 19 cm -3 ; S43, in Al z Ga 1-z The P-type doped GaAs metal contact layer with a thickness of 20-500 nm was grown on the As confinement layer using molecular beam epitaxy at a growth rate of 0.1-1 ML / s at a chamber temperature of 500-700°C. The P-type doping concentration was 1×10 18 ~5×10 19 cm -3 .

9. The method for growing a multi-layer quantum dot laser according to claim 8, characterized in that: The concentration of P-type doping in S42 is 5×10 17 cm -3 ; The concentration of P-type doping in S43 is 2×10 19 cm -3 .

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